(1) Namaste, Berwyn's comment is very astute: on such a long flight, super-popular routes: it will be kind of "normal" if you miss a connection, and it won't matter at all, they'll just put you on another. Your flight is so long you won't even notice if you arrive the odd day after the supposed original arrival time
(2) For Munich no problem
(3) For LHR you must state your arrival/departure terminals
At Heathrow - the most horrific, sickening, soul-destroying anything in the solar system - transfers are often a marthon
(4) Thank God, you DID book on one complete ticket with one airline (right?) You have nothing to worry about, they'll just put you on a next flight if there's a screw-up.
Tip: pick aisle seats
(5) the food is crap on Lufthansa's India->Frankfort legs :/
(6) You should have flown Emirates dude. It's not even more expensive.
If a corporate travel department booked this disaster, you got screwed :/ I'm sorry.